CVE•Published 2021-05-25•Modified 2026-10-14•1 article on news•6 live references•NVD data

CVE-2021-33574Gnu · Glibc

Vulnerability data via NVD (ingested)

CVSS v3.1

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS percentile

Exploit Prediction Scoring System · top 14% of all CVEs

Weaknesses (CWE)

CWE-416Use After Free

Description

The mq_notify function in the GNU C Library (aka glibc) versions 2.32 and 2.33 has a use-after-free. It may use the notification thread attributes object (passed through its struct sigevent parameter) after it has been freed by the caller, leading to a denial of service (application crash) or possibly unspecified other impact.

Timeline

Published 2021-05-25

Modified 2026-10-14

External references

NVD MITRE Exploit-DB GitHub PoC trickest/cve VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).

Shodan · vuln tag0 hosts

vuln:CVE-2021-33574

Hosts Shodan has explicitly fingerprinted as vulnerable.

Shodan · product + version

product:"Gnu Glibc" version:"2.32"

Version-pinned fingerprint from NVD's first vulnerable CPE.

Shodan · banner/body mention

http.html:"Glibc"

HTTP body or banner mentions "Glibc" — catches deploys Shodan didn't identify as a product.

More intel sources (5)

Shodan report

vuln:CVE-2021-33574